Climate contributions to vegetation variations in Central Asian drylands: Pre- and post-USSR collapse

Research output: Contribution to journalArticle

Abstract

Central Asia comprises a large fraction of the world's drylands, known to be vulnerable to climate change. We analyzed the inter-annual trends and the impact of climate variability in the vegetation greenness for Central Asia from 1982 to 2011 using GIMMS3g normalized difference vegetation index (NDVI) data. In our study, most areas showed an increasing trend during 1982-1991, but experienced a significantly decreasing trend for 1992-2011. Vegetation changes were closely coupled to climate variables (precipitation and temperature) during 1982-1991 and 1992-2011, but the response trajectories differed between these two periods. The warming trend in Central Asia initially enhanced the vegetation greenness before 1991, but the continued warming trend subsequently became a suppressant of further gains in greenness afterwards. Precipitation expanded its influence on larger vegetated areas in 1992-2011 when compared to 1982-1991. Moreover, the time-lag response of plants to rainfall tended to increase after 1992 compared to the pre-1992 period, indicating that plants might have experienced functional transformations to adapt the climate change during the study period. The impact of climate on vegetation was significantly different for the different sub-regions before and after 1992, coinciding with the collapse of the Union of Soviet Socialist Republics (USSR). It was suggested that these spatio-temporal patterns in greenness change and their relationship with climate change for some regions could be explained by the changes in the socio-economic structure resulted from the USSR collapse in late 1991. Our results clearly illustrate the combined influence of climatic/anthropogenic contributions on vegetation growth in Central Asian drylands. Due to the USSR collapse, this region represents a unique case study of the vegetation response to climate changes under different climatic and socio-economic conditions.

Details

Authors
  • Yu Zhou
  • Li Zhang
  • Rasmus Fensholt
  • Kun Wang
  • Irina Vitkovskaya
  • Feng Tian
External organisations
  • University of the Chinese Academy of Sciences
  • University of Copenhagen
  • Institute of Remote Sensing and Digital Earth, CAS
  • National Centre of Space Research and Technology of the Republic of Kazakhstan
  • School of Environment Science and Spatial Informatics
  • China University of Mining Technology
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Earth and Related Environmental Sciences

Keywords

  • Climate change, GIMMS3g NDVI, USSR collapse, Vegetation greenness
Original languageEnglish
Pages (from-to)2449-2470
Number of pages22
JournalRemote Sensing
Volume7
Issue number3
Publication statusPublished - 2015 Jan 1
Publication categoryResearch
Peer-reviewedYes
Externally publishedYes